Update - November 2021

Late rains have resulted in an increase in nutrients in the lakes, and this has contributed to midge and mosquitoes breeding. We understand the impact this has had on residents surrounding the lakes, and we are taking action.

the GHD report identified dredging will remove nutrients and the feedback from residents and the results of midge larvae sampling indicated the dredging of Lake Bungana resulted in lower levels of midge, so the City will dredge Lake Brearley in early February 2022. This is later than we had planned, however a specialist contractor is required and they are not available until this date.

Large mechanical mixers in Lake Brearley and Lake Bungana are in the process of being commissioned and are expected to be fully operational prior to Christmas. The mixers will increase oxygen in deeper water and create less favourable conditions for nutrients to be released from the sediment. This is a sustainable, cost and energy effective approach using an established technology.

In September, the City installed two solar powered ultrasonic devices in Lake Brearley as part of a twelve month trial. Early field observations indicate they are making a positive impact, with a reduction in floating algae slicks and the reduced build up of algae around the edges of the lake.

The City is also continuing to use larvicide treatments to reduce midge numbers; and is monitoring water quality so we can measure the effectiveness of these actions.

Unfortunately, there isn’t just one solution to the issues being experienced, but we are committed to following the advice of GHD and working with the community to achieve the best possible outcome.